Accept SDP with TRANSPORT attributes missing from bundled m= sections.

webrtc/p2p/base/transportdescriptionfactory.h

 /*
  *  Copyright 2012 The WebRTC Project Authors. All rights reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 35 matching lines @@
   // Specifies the certificate to use (only used when secure != SEC_DISABLED).
   void set_certificate(
       const rtc::scoped_refptr<rtc::RTCCertificate>& certificate) {
     certificate_ = certificate;
   }
 
   // Creates a transport description suitable for use in an offer.
   TransportDescription* CreateOffer(const TransportOptions& options,
       const TransportDescription* current_description) const;
   // Create a transport description that is a response to an offer.
+  // |bundled| indicates that this transport description is being generated
+  // for an m= section that's being bundled into another m= section, in

[pthatcher1, 2017/02/17 19:17:32]

might be more clear as 

"|bundled| indicates that this transport description is in an m= section that's
in a bundle group and isn't the first m= section in the bundle group, so it
doesn't need transport-level attributes".

Better yet, why not just call the variable |include_transport_level_attributes|
or some shorter version of that?  Then you don't need the comment.

[Taylor Brandstetter, 2017/02/17 21:49:14]

Done.

+  // which case transport-level attributes aren't needed since they can
+  // be found in the other m= section.
   TransportDescription* CreateAnswer(
       const TransportDescription* offer,
       const TransportOptions& options,
-      const TransportDescription* current_description) const;
+      const TransportDescription* current_description,
+      bool bundled) const;

[pthatcher1, 2017/02/17 19:17:32]

It ought to be the 3rd argument, not the last.  And maybe it should be part of
TransportOptions.

[Taylor Brandstetter, 2017/02/17 21:49:14]

Done (though not the TransportOptions part).

 
  private:
   bool SetSecurityInfo(TransportDescription* description,
                        ConnectionRole role) const;
 
   SecurePolicy secure_;
   rtc::scoped_refptr<rtc::RTCCertificate> certificate_;
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_P2P_BASE_TRANSPORTDESCRIPTIONFACTORY_H_